So far, most high manganese steels do not add other alloy elements. When there are higher requirements for the material, you can choose grades containing chromium, molybdenum, nickel, etc.
① Part of the molybdenum in high manganese steel is dissolved in austenite, and part forms primary carbides when the casting solidifies. Molybdenum dissolved in austenite can effectively inhibit the formation of brittle carbides and pearlite, and improve the yield strength and toughness after water toughening. Molybdenum in primary carbides can change the distribution of carbides, from network carbides precipitated along the grain boundaries to spherical ones. The steel has high strength and wear resistance is also improved.
② Chromium is added to high manganese steel mainly to increase the yield strength, but after adding chromium, the number of network carbides on the austenite grain boundaries increases, and the tensile strength and elongation decrease.
Whether adding chromium to high manganese steel can improve the wear resistance of steel has not been confirmed so far. Further research is needed.
③ Adding nickel to high manganese steel can stabilize austenite and effectively inhibit the precipitation of carbide lamellar crystals, but it has no strengthening effect on steel. Nickel in high manganese steel helps to maintain non-magnetic properties, especially to keep the decarburized layer of castings non-magnetic. Therefore, nickel is mainly used in high manganese steel as a non-magnetic material.
④ Vanadium is a strong carbide-forming element that can form fine carbides, thereby significantly improving the yield strength of steel, but the toughness and plasticity of steel will be reduced. It can only be applied to some special working conditions, and the addition amount generally does not exceed 0.5%.
⑤ The role of copper in high manganese steel is similar to that of nickel, which can stabilize austenite. The effect of copper on mechanical properties is still unclear. Studies have pointed out that the solubility of copper in high manganese steel is limited, and a slightly larger addition can cause embrittlement of steel.
Titanium carbide ceramics, as a typical transition metal carbide, is usually used as a reinforcing phase in composite materials, and more often with Molybdenum, Nickle as its binder phase.
